The best child health care outcomes are achieved through evidence-based practice. Evidence-based practice, however, requires practice-based evidence, and the coalitions of primary care practices and clinics known as practice-based research networks (PBRNs) have provided some of the highest quality and most generalizable practice-based evidence. PBRNs face numerous problems, however, in conducting important and timely research in primary care settings. Principal challenges include (1) maintaining an infrastructure to address the complex work of primary care research; (2) amassing a large enough cohort of member practices to address the sample size issues presented by data clustering; and (3) aggregating a knowledgeable and sophisticated cohort of researchers with the expertise needed to conduct practice-based research. Individual pediatric PBRNs have dealt and partially solved some of these challenges, but none have been able to address them fully. The Specific Aims of this project are: 1. Link two pediatric PBRNs: Pediatric Research in Office Settings (PROS), the PBRN of the American Academy of Pediatrics (AAP) - the nation's largest and second oldest pediatric PBRN (enhanced by its affiliation with the AAP's Quality Improvement Innovation Network (QuIlN)), and the Pediatric Research Consortium (PeRC) of the Children's Hospital of Philadelphia (CHOP) - t h e nation's most innovative pediatric PBRN, in a national center for pediatric practice-based research and learning. 2. Enhance established and create new working relationships between PROS/AAP and PeRC/CHOP 3. Leverage the dissemination and implementation capacities of PROS and PeRC and their parent organizations to improve delivery of pediatric primary care at local, regional, and national levels. These aims will be achieved through coordinated activities of center administrative and research cores allowing for responses to rapid-cycle funding opportunity announcements as well as the development of investigator-initiated primary care research. PUBLIC HEALTH RELEVANCE: This project promises to generate new knowledge to advance the field of primary care pediatrics by allying two of the most successful pediatric practice-based research networks. The networks' enhanced infrastructure will support not only knowledge creation, but also knowledge dissemination and direct efforts to implement evidence-based pediatric care.